package demo07;
//键盘就是一个USB设备
public class Keyboard implements USB
{ @Override
public void open() {
    System.out.println("打开键盘");
}

    @Override
    public void close() {
        System.out.println("关闭键盘");
    }
    public void type(){
        System.out.println("键盘输入");
    }
}
